Punjab Agricultural University, Ludhiana, Punjab
A three year field study was conducted on two different soils to relate the yield of winter wheat and pre-irrigation soil-water depletion (SWD). Wheat sown after pre-planting irrigation received its first post-planting irrigation within 30 days. Subsequent irrigations were applied at SWD ranging between 5 to 17 cm/180 cm. On a soil of lower retentive capacity the grain yield declined when SWD exceeded 11 cm while on soil of higher retentive capacity the yield was unaffected up to a depletion of 17 cm. Thus, for potential yield of wheat the available water storage of these soils is 11 and 17 cm, respectively. A specified amount of water, equal to or less than the available water storage thus defined for a combination of crop, soil and climate, may be applied at equivalent depletion to get optimum yield of the crop under given conditions.
Pre-irrigation soil—water depletion, available water capacity of soil for potential yields, irrigation scheduling
